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Scintillation detector efficiencies for neutrons in the energy region above 20 MeV

Description: The computer program SCINFUL (for SCINtillator FUL1 response) is a program designed to provide a calculated complete pulse-height response anticipated for neutrons being detected by either an NE-213 (liquid) scintillator or an NE-110 (solid) scintillator in the shape of a right circular cylinder. The point neutron source may be placed at any location with respect to the detector, even inside of it. The neutron source may be monoenergetic, or Maxwellian distributed, or distributed between chosen lower and upper bounds. The calculational method uses Monte Carlo techniques, and it is relativistically correct. Extensive comparisons with a variety of experimental data have been made. There is generally overall good agreement (less than 10% differences) of results for SCINFUL calculations with measured integral detector efficiencies for the design incident neutron energy range of 0.1 to 80 MeV. Calculations of differential detector responses, i.e. yield versus response pulse height, are generally within about 5% on the average for incident neutron energies between 16 and 50 MeV and for the upper 70% of the response pulse height. For incident neutron energies between 50 and 80 MeV, the calculated shape of the response agrees with measurements, but the calculations tend to underpredict the absolute values of the measured responses. Extension of the program to compute responses for incident neutron energies greater than 80 MeV will require new experimental data on neutron interactions with carbon. 32 refs., 6 figs., 2 tabs.
Date: January 1, 1991
Creator: Dickens, J.K.
Partner: UNT Libraries Government Documents Department

Design optimization of liquid scintillator cosmic-ray veto detector with BBQ shifter

Description: Certain design characteristics of a liquid scintillator detector for charged cosmic particles, have been studied. These include evaluation of scintillator emission spectra, absorption in various thicknesses of BBQ shifter bars and effective transmission in long lengths of BBQ acrylic. For our BBQ sample, 12.5 mm thick with semicircular shape, the shifted light was transmitted with 2.0 m absorption length.
Date: October 1, 1981
Creator: Kruse, H.W.; Egdorf, S.S. & Simmons, D.F.
Partner: UNT Libraries Government Documents Department

Multi-energy neutron detector for counting thermal neutrons, high-energy neutrons, and gamma photons separately

Description: The need for an improved, compact, wide-energy neutron detector for neutron monitoring and surveillance in nuclear facilities and weapons storage, where a possibility of fission excursion exists, led to development of a single detector that is sensitive to thermal neutrons, high-energy neutrons, and gamma radiation. Previously, separate detectors have been required to count these three different radiations separately. This development is a great advantage when experimental space is limited. 4 figs.
Date: January 1, 1989
Creator: Chiles, M.M. & McElhaney, S.A.
Partner: UNT Libraries Government Documents Department

Tritium monitoring system for near ambient measurements

Description: This paper describes the current status of research on an improved tritium measurement system at the Oak Ridge National Laboratory (ORNL) for the US Navy. Present tritium-in-air monitoring systems installed by the Navy can reliably measure to less than 10 {mu}Ci/m{sup 3}, but medical and safety issues are pushing measurement needs to below 1 {mu}Ci/m{sup 3}, which is equivalent to 1--10 nCi/ml in liquid samples, using calcium metal converter. A significant effort has been expended over the past 10 years by the Navy RADIAC Development Program at ORNL on various schemes to improve the detection of tritium in both air and liquid at near ambient levels. One such scheme includes a liquid flow-through system based on an NE102 sponge scintillator with dual photomultiplier tubes for the tube noise rejection. (This document also contains copies of the slides used for presentation of this paper to the IEEE 1991 Nuclear Science Symposium). 4 refs., 17 figs.
Date: January 1, 1991
Creator: Falter, K.G. & Bauer, M.L.
Partner: UNT Libraries Government Documents Department

Experiment to investigate anti. nu. /sub. mu. /. -->. anti. nu. /sub e/ oscillations at Los Alamos Meson Physics Facility

Description: An experiment, being planned at LAMPF, aims to investigate a possible neutrino oscillation channel, anti ..nu../sub ..mu../ ..-->.. anti ..nu../sub e/. If anti ..nu../sub ..mu../, produced in the LAMPF beam stop, oscillate to anti ..nu../sub e/, then interactions anti ..nu../sub e/ + p ..-->.. e/sup +/ + n, may be detected. A large volume liquid scintillator (4470 liter) emplaced at 33 m from the beam stop, detects e/sup +/ and n, after moderation in the hydrogenous liquid and capture in Gd, loaded into the scintillator. Our anticipated signal rate is currently estimated at 1.67 (sigma m/sup 2/)/sup 2//day assuming full amplitude oscillation. The corresponding counting rate, assuming all anti ..nu../sub ..mu../ have oscillated to anti ..nu../sub e/ at the detector is 1.5/day. Cosmic rates are estimated at 0.033/day. Correlated backgrounds from the beam stop are calculated to be small in comparison to cosmic events, except for reactions of ..nu../sub e/ in Pb. These reactions may be reduced with an Fe shield within the detector. With the above rate, a limit on the sensitivity of our experiment for the value of sigma m/sup 2/ is estimated at 0.12 eV/sup 2/ with 70 days of counting. Detector features, estimated background rates, and sensitivity values are discussed.
Date: January 1, 1981
Creator: Kruse, H.W. & Toevs, J.W.
Partner: UNT Libraries Government Documents Department

Instrumentation for medical diagnosis and research with radionuclides in the developing countries. Progress report, June 1, 1977--May 31, 1978

Description: This project seeks to bring about a more effective use of nuclear instruments in medical applications of radionuclides in developing countries by facilitating selection of appropriate applications, by stimulating the design of instruments capable of performing these applications satisfactorily under the conditions prevailing, and by encouraging improved maintenance. A pilot cost-effectiveness analysis of nuclear medicine applications has been completed, suggesting two topics for further investigation and demonstrating that such analyses can yield useful insights. In the realm of instrument design, we have further developed our prototype well scintillation counter, provided three such instruments for tests in the field, and encouraged its production by others. In addition, we have examined design issues for liquid scintillation counters, radiorespirometry counting devices, whole-body counters, and electrical power supplies. We have completed a survey of maintenance in 8 countries in Southeast Asia and are analyzing the results. Preparations are underway for surveys in three further regions.
Date: July 1, 1978
Creator: Dudley, R.A.
Partner: UNT Libraries Government Documents Department

Antineutrino detector for anti. nu. oscillation studies at fission weapon tests and at LAMPF

Description: Two anti ..nu.. oscillation experiments are planned, incorporating large volume (4200 l) liquid scintillation detectors 1) at large distances (450 to 800 m) from fission weapon tests and 2) at 12 to 50 m from LAMPF beam dump where significant anti ..nu../sub e/ events are detected only if some oscillation operates, such as ..nu../sub ..mu../ ..-->.. ..nu../sub e/. Design criteria, detector characteristics, and experimental considerations are given.
Date: January 1, 1980
Creator: Kruse, H.W.; Loncoski, R. & Mack, J.
Partner: UNT Libraries Government Documents Department

Progress report of a research program in experimental and theoretical high energy physics, 1 June 1992--May 31, 1993

Description: The main emphasis in the theoretical program has been in the area of string theory; also investigated were confinement and other aspects of QCD, electroweak symmetry breaking, and electroweak baryogenesis. The research program in computational physics concentrated on the development of the source Galerkin method of numerical quantum field theory. One portion of the experimental program dealt with interactions of leptons and hadrons from accelerator and strophysics sources. A description of the Large Volume Detector at Gran Sasso and its use as a stellar collapse monitor is given, along with an account of research and development on resistive plate counters. The rest of the experimental program concerns hadron collider and neutrino physics, with major emphasis on the D0 experiment at the TeVatron. The commissioning of the D0 detector and its operation are described, along with D0 analysis. Also reported is a novel cryogenic technique utilizing superfluid helium for neutrino calorimetry. 122 refs., 7 tabs., 23 figs.
Date: June 1, 1993
Creator: Brandenberger, R.; Cutts, D. & Fried, H. M.
Partner: UNT Libraries Government Documents Department

Studies of nuclei using radioactive beams. [Space Astronomy Lab., Univ. of Florida, Gainesville, Florida]

Description: The 12 month period from May 1988 to July 1989 represents the first full year of our 18 month pilot program in nuclear structure research. In this period, research was initiated to develop a capability for radioactive secondary beams at Argonne National Laboratory using the Atlas and the new Fragment Mass Analyzer (FMA), which is currently under construction. Two major new detector facilities are currently in the final stages of design and testing. The Large-Area, Scintillator Telescope (LAST) detector is fully operational and will be shipped to Argonne National Laboratory in August for fit-tests and in-beam calibrations. The first segments of a new sixteen-segment neutron multiplicity detector have been built and tested. The remaining segments are currently being constructed. Research was continued in the areas of (1) Coulomb excitation studies of rare earth and actinide nuclei; (2) In-beam, gamma-ray spectroscopy of nuclei in the mass 100 region, and (3) Advanced detector design. Several journal articles and abstracts were published or submitted for publication in the reporting period, and others are currently in preparation. Three graduate students participated in the program, one from the University of Florida and two from the Royal Institute of Technology, Stockholm, Sweden.
Date: July 1, 1989
Creator: Piercey, R .B.
Partner: UNT Libraries Government Documents Department

Experimental particle physics. Progress report, September 16, 1991--September 30, 1992

Description: The goals of this research are the experimental testing of fundamental theories of physics beyond the standard model and the exploration of cosmic phenomena through the techniques of particle physics. We are working on the MACRO experiment, which employs a large-area underground detector to search fore grand unification magnetic monopoles and dark matter candidates and to study cosmic ray muons as well as low- and high-energy neutrinos; the Chooz experiment to search for reactor neutrino oscillations at a distance of 1 km from the source; a new proposal (the Perry experiment) to construct a one-kiloton liquid scintillator in the Fairport, Ohio underground facility IMB to study neutrino oscillations with a 13 km baseline; and development of technology for improved liquid scintillators and for very-low-background materials in support of the MACRO and Perry experiments and for new solar neutrino experiments.
Date: September 1, 1992
Creator: Steinberg, R. I. & Lane, C. E.
Partner: UNT Libraries Government Documents Department

Neutrino proton scattering and the isosinglet term

Description: Elastic neutrino proton scattering is sensitive to the SU(3) axial isosinglet term which is in turn dependent on the strangeness content of the proton. The uncertainties in the analysis of a neutrino proton elastic scattering experiment are discussed, and an experiment which is insensitive to many of the difficulties of the previous experiment is described.
Date: January 1, 1990
Creator: White, D.H.
Partner: UNT Libraries Government Documents Department

Studies of nuclei using radioactive beams. Progress report, May 1988--July 1989

Description: The 12 month period from May 1988 to July 1989 represents the first full year of our 18 month pilot program in nuclear structure research. In this period, research was initiated to develop a capability for radioactive secondary beams at Argonne National Laboratory using the Atlas and the new Fragment Mass Analyzer (FMA), which is currently under construction. Two major new detector facilities are currently in the final stages of design and testing. The Large-Area, Scintillator Telescope (LAST) detector is fully operational and will be shipped to Argonne National Laboratory in August for fit-tests and in-beam calibrations. The first segments of a new sixteen-segment neutron multiplicity detector have been built and tested. The remaining segments are currently being constructed. Research was continued in the areas of (1) Coulomb excitation studies of rare earth and actinide nuclei; (2) In-beam, gamma-ray spectroscopy of nuclei in the mass 100 region, and (3) Advanced detector design. Several journal articles and abstracts were published or submitted for publication in the reporting period, and others are currently in preparation. Three graduate students participated in the program, one from the University of Florida and two from the Royal Institute of Technology, Stockholm, Sweden.
Date: July 1, 1989
Creator: Piercey, R. B.
Partner: UNT Libraries Government Documents Department

High Energy Physics Program at Texas A and M University. Annual report, November 1, 1991--October 31, 1992

Description: The high energy physics program has continued its experimental activities over. In CDF, the Texas A&M group has led an effort to design an upgrade for the silicon vertex detector, and is currently working with the rest of the collaboration on the next major data taking run. In MACRO, work was done on the development of the final version of the wave form digitizing system being implemented for the entire scintillator system. This work is nearing completion, and the system is expected to be up and running on the detector by summer 1993. Work was done within the SDC group to develop gas microstrip chambers for use in precision tracking at the SSC, and in the GEM group, toward the development of a suitable forward calorimeter design. The theoretical high energy physics program has continued the study of a very successful string-derived model that unifies all known interactions: flipped SU(5), which is the leading candidate for a TOE. Work has also continued on some generalizations of the symmetries of string theory, known as W algebras. These are expected to have applications in two-dimensional conformal field theory, two-dimensional extensions of gravity and topological gravity and W-string theory.
Date: November 1, 1992
Partner: UNT Libraries Government Documents Department

Collider Physics: SDC/SSC liquified fiber calorimetry. Progress report, 1992

Description: Most effort was directed toward the D-Zero experiment at Fermilab. Over 3 pb{sup {minus}1} of high-quality physics data have been obtained. Analysis of the results (wino-zino physics, squark physics), D-zero data acquisition systems efforts, and level-1 and level-2 trigger work are described. Other work concerned detector development for use at the SSC. This technology consists of using liquid scintillator-filled tubes as scintillating fibers for a ``calorimeter.`` The key issues were to demonstrate that the liquid fibers were sufficiently rad-hard and to demonstrate that fibers with sufficiently long attenuation length could be found to satisfy the resolution requirements; both constraints could be satisfied.
Date: December 31, 1992
Creator: White, J. T. & Huson, F. R.
Partner: UNT Libraries Government Documents Department

Neutron spectra as a function of angle at two meters from the Little Boy assembly

Description: Measurements of neutron spectra produced by the Los Alamos National Laboratory (LANL) Little Boy replica assembly (Comet) were made with a combined multisphere and liquid scintillator system, that has been widely used at the Lawrence Livermore National Laboratory. The combined system was used for measurements at the side (90/sup 0/) and nose (0/sup 0/) of the assembly; additional measurements were made at 45/sup 0/ using only the liquid scintillator. Data were obtained at two meters from the center of the reactive region of the assembly, with good agreement between the multisphere and scintillator results. Comparison with liquid scintillator measurements performed by experimenters from the Canadian Defence Research Establishment, Ottawa (DREO) and calculations from LANL depended on the specific angle, obtaining the best agreement at 90/sup 0/. 32 references, 11 figures, 4 tables.
Date: July 2, 1984
Creator: Griffith, R.V.; Huntzinger, C.J. & Thorngate, J.H.
Partner: UNT Libraries Government Documents Department

Interface for routine spectral display from several liquid scintillation counters

Description: An interfacing circuit for coupling several Tri-Carb liquid scintillation counters to a multichannel analyzer is described. The display of the analyzer is completely controlled from the liquid scintillation counters and information from any one of the three channels in each counter can be displayed. The system is being used for both instructional and diagnostic purposes. For the former it will be part of a course on the theory and use of liquid scintillation counting. For the latter it assists in setting up optimum counting conditions for single and double labels in new cocktails as well as for new labels, and to help diagnose counting problems such as chemi- and/or photoluminescence.
Date: April 1, 1976
Creator: Gordon, B. E.; Press, M.; Erwin, W. & Lemmon, R. M.
Partner: UNT Libraries Government Documents Department

Note on the experimental determination of the relative fast-neutron sensitivity of a hydrogenous scintillator

Description: A method for determining the relative fast-neutron sensitivity of a hydrogenous scintillator is outlined. The procedure is based upon the time-of-flight measurement of the prompt-fission-neutron spectrum of /sup 252/Cf. Detailed relative detector sensitivities are experimentally determined to few percent accuracies for neutron energies from a few 100 keV to 10 MeV.
Date: June 1, 1976
Creator: Smith, A.; Guenther, P. & Sjoblom, R.
Partner: UNT Libraries Government Documents Department

Alternating sample changer and an automatic sample changer for liquid scintillation counting of alpha-emitting materials

Description: Two sample changers are described that were designed for liquid scintillation counting of alpha-emitting samples prepared using solvent-extraction chemistry. One operates manually but changes samples without exposing the photomultiplier tube to light, allowing the high voltage to remain on for improved stability. The other is capable of automatically counting up to 39 samples. An electronic control for the automatic sample changer is also described.
Date: August 1, 1977
Creator: Thorngate, J. H.
Partner: UNT Libraries Government Documents Department

Response of NE-228A, NE-228, NE-224, and NE-102 scintillators to protons from 2. 43 to 19. 55 MeV

Description: A T(d,n)..cap alpha.. neutron source at the Ohio University tanden Van de Graaff accelerator was used to produce a coincidence in the detector setup and the recoil proton pulse was recorded. Results are presented. (WHK)
Date: January 1, 1975
Creator: Madey, R.; Waterman, F. M.; Baldwin, A. R.; Carlson, J. D. & Rapaport, J.
Partner: UNT Libraries Government Documents Department

Lepton detector workshop summary

Description: The study group met from June 7 to 11, 1976, with the dual purpose of reviewing an earlier Lepton Detector report in order to resolve some of the remaining design problems and of considering possible alternatives. Since the role of this group was primarily that of providing a critique of the earlier work, the reader is referred to that earlier paper for the general motivation and design of the detector. Problems studied at this session are described.
Date: January 1, 1976
Creator: Imlay, R.; Iwata, S. & Thorndike, A.
Partner: UNT Libraries Government Documents Department

NUTSPEC: a program for unfolding neutron spectral data obtained with scintillation detectors and gas proportional counters

Description: NUTSPEC, an interactive program available on the LLL CDC 7600 Octopus Network computers, unfolds neutron spectral data obtained with NE213 and stilbene scintillation detectors, as well as CH/sub 4/, H/sub 2/, and /sup 3/He gas proportional counters. This document explains how to obtain and execute the program, and describes the input and output data formats used by NUTSPEC. Examples of input files and output plots, along with the user/program interactions, are shown. NUTSPEC also has various graphical display capabilities (TMDS, RJET, FR80).
Date: January 30, 1978
Creator: Slaughter, D.R.
Partner: UNT Libraries Government Documents Department

Simple method to unfold NE 213 and stilbene neutron spectral data

Description: A very simple method is proposed wherein recoil proton scintillation data are reduced using the derivative unfolding technique. The approximations described require minimal calculation or storage and may be readily implemented on a mini computer. A digital filter is incorporated which yields a smoothed approximation to the slope of the pulse-height distribution, with error estimates. In order to accurately represent the scintillator light output without introducing discontinuities in the unfolded spectrum, the light output data are fitted using B-splines whose first and second derivatives are continuous.
Date: April 1, 1976
Creator: Slaughter, D. R.
Partner: UNT Libraries Government Documents Department

Search for neutrino oscillations at the Brookhaven AGS

Description: We report on a search for neutrino oscillations of the type nu/sub ..mu../ ..-->.. nu/sub e/ in a detector located an effective distance of 96m from the neutrino source in the wide band neutrino beam at the Brookhaven AGS. No excess of electron events was observed. The resulting upper limit on the strength of the mixing between nu/sub ..mu../ and nu/sub e/ in the case of large mass difference ..delta..m/sup 2/ = absolute value m/sub 1//sup 2/ - m/sub 2//sup 2/ between the neutrino mass eigenstates m/sub 1/ and m/sub 2/ is sin/sup 2/2..cap alpha.. less than or equal to 3.4 x 10/sup -3/ at 90% CL. The corresponding upper limit for small mass difference is ..delta..m/sup 2/sin2..cap alpha.. < 0.43 eV/sup 2/. 9 refs.
Date: February 20, 1985
Creator: Ahrens, L.A.; Aronson, S.H.; Connolly, P.L.; Gibbard, B.G.; Murtagh, M.J.; Murtagh, S.J. et al.
Partner: UNT Libraries Government Documents Department